288 research outputs found
Biology and Conservation of Horseshoe Crabs
We dedicate this book to Drs. Carl N. Shuster, Jr. and Koichi Sekiguchi for their life-long contributions to the biology and conservation of the magnificent horseshoe crab
Smartphone scene generator for efficient characterization of visible imaging detectors
Full characterization of imaging detectors involves subjecting them to
spatially and temporally varying illumination patterns over a large dynamic
range. Here we present a scene generator that fulfills many of these functions.
Based on a modern smartphone, it has a number of good features, including the
ability to generate nearly arbitrary optical scenes, high spatial resolution
(13 um), high dynamic range (~10^4), near-Poisson limited illumination
stability over time periods from 100 ms to many days, and no background noise.
The system does not require any moving parts and may be constructed at modest
cost. We present the optical, mechanical, and software design, test data
validating the performance, and application examples.Comment: 14 pages. This version includes code, available here:
https://github.com/Leo-Nea
Smartphone screens as astrometric calibrators
Geometric optical distortion is a significant contributor to the astrometric
error budget in large telescopes using adaptive optics. To increase astrometric
precision, optical distortion calibration is necessary. We investigate using
smartphone OLED screens as astrometric calibrators. Smartphones are low cost,
have stable illumination, and can be quickly reconfigured to probe different
spatial frequencies of an optical system's geometric distortion. In this work,
we characterize the astrometric accuracy of a Samsung S20 smartphone, with a
view towards providing large format, flexible astrometric calibrators for the
next generation of astronomical instruments. We find the placement error of the
pixels to be 189 nm +/- 15 nm RMS. At this level of error, milliarcsecond
astrometric accuracy can be obtained on modern astronomical instruments.Comment: 15 pages, 11 figures; accepted, Journal of Astronomical
Instrumentatio
The High-Flux Backscattering Spectrometer at the NIST Center for Neutron Research
We describe the design and current performance of the high-flux
backscattering spectrometer located at the NIST Center for Neutron Research.
The design incorporates several state-of-the-art neutron optical devices to
achieve the highest flux on sample possible while maintaining an energy
resolution of less than 1mueV. Foremost among these is a novel phase-space
transformation chopper that significantly reduces the mismatch between the beam
divergences of the primary and secondary parts of the instrument. This resolves
a long-standing problem of backscattering spectrometers, and produces a
relative gain in neutron flux of 4.2. A high-speed Doppler-driven monochromator
system has been built that is capable of achieving energy transfers of up to
+-50mueV, thereby extending the dynamic range of this type of spectrometer by
more than a factor of two over that of other reactor-based backscattering
instruments
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Joint University Council Public Accounts Committee position statement – QAA subject benchmarks for business and management 2021 (in collaboration with BAM and PSA Special Interest Groups)
Since 2015, the date of the last QAA subject benchmark review, the socio-economic context has changed, and the speed of that change continues to accelerate. Within this, the relationship between public, private and not-for-profit sectors, and the relationship between individuals (as consumers and citizens) and organisations, has changed. This has created new challenges and there has been a greater need for partnership working. Consequently, there is a greater need for more explicit knowledge, understanding and skills that focus on these new interdependencies, organisations and sectoral differences
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REF 2028 initial decisions survey. UKAPA response
The four UK higher education funding bodies (Research England, SFC, HEFCW and DfE (NI) are publishing key decisions on the high-level design of the next research assessment exercise and outlining issues for further consultation. These decisions represent a shift towards a broader and more holistic approach to research assessment. This survey is hosted by Research England (part of UKRI) on behalf of the four UK funding bodies. The survey is available as a downloadable PDF for convenience (see below).
This is the response from UKAPA (United Kingdom Association for Public Administration - the Learned Society for PA
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Joint University Council Public Accounts Committee position statement - REF post-2021 (in collaboration with BAM and PSA Special Interest Groups)
A position statement agreed by the JUC Public Administration Committee in collaboration with the British Academy of Management and the Political Studies Association (PA Special Interest Groups), about the future position of Public administration and management following the 2021 Research Excellence Frameworks completio
Improving the Information Security Model by using TFI
In the context of information systems and information technology, information security is a concept that is becoming widely used. The European Network of Excellence INTEROP classifies information security as a nonfunctional aspect of interoperability and as such it is an integral part of the design process for interoperable systems. In the last decade, academics and practitioners have shown their interest in information security, for example by developing security models for evaluating products and setting up security specifications in order to safeguard the confidentiality, integrity, availability and accountability of data. Earlier research has shown that measures to achieve information security in the administrative or organisational level are missing or inadequate. Therefore, there is a need to improve information security models by including vital elements of information security. In this paper, we introduce a holistic view of information security based on a Swedish model combined with a literature survey. Furthermore we suggest extending this model using concepts based on semiotic theory and adopting the view of an information system as constituted of the technical, formal and informal (TFI) parts. The aim is to increase the understanding of the information security domain in order to develop a well-founded theoretical framework, which can be used both in the analysis and the design phase of interoperable systems. Finally, we describe and apply the Information Security (InfoSec) model to the results of three different case studies in the healthcare domain. Limits of the model will be highlighted and an extension will be proposed.In the context of information systems and information technology, information security is a concept that is becoming widely used. The European Network of Excellence INTEROP classifies information security as a nonfunctional aspect of interoperability and as such it is an integral part of the design process for interoperable systems. In the last decade, academics and practitioners have shown their interest in information security, for example by developing security models for evaluating products and setting up security specifications in order to safeguard the confidentiality, integrity, availability and accountability of data. Earlier research has shown that measures to achieve information security in the administrative or organisational level are missing or inadequate. Therefore, there is a need to improve information security models by including vital elements of information security. In this paper, we introduce a holistic view of information security based on a Swedish model combined with a literature survey. Furthermore we suggest extending this model using concepts based on semiotic theory and adopting the view of an information system as constituted of the technical, formal and informal (TFI) parts. The aim is to increase the understanding of the information security domain in order to develop a well-founded theoretical framework, which can be used both in the analysis and the design phase of interoperable systems. Finally, we describe and apply the Information Security (InfoSec) model to the results of three different case studies in the healthcare domain. Limits of the model will be highlighted and an extension will be proposed.Monograph's chapter
Effect of Salt on Phosphorylcholine-based Zwitterionic Polymer Brushes.
A quantitative investigation of the responses of surface-grown biocompatible brushes of poly(2-(methacryloyloxy)ethyl phosphorylcholine) (PMPC) to different types of salt has been carried out using ellipsometry, quartz crystal microbalance (QCM) measurements, and friction force microscopy. Both cations and anions of varying valency over a wide range of concentrations were examined. Ellipsometry shows that the height of the brushes is largely independent of the ionic strength, confirming that the degree of swelling of the polymer is independent of the ionic character of the medium. In contrast, QCM measurements reveal significant changes in mass and dissipation to the PMPC brush layer, suggesting that ions bind to phosphorylcholine (PC) groups in PMPC molecules, which results in changes in the stiffness of the brush layer, and the binding affinity varies with salt type. Nanotribological measurements made using friction force microscopy show that the coefficient of friction decreases with increasing ionic strength for a variety of salts, supporting the conclusion drawn from QCM measurements. It is proposed that the binding of ions to the PMPC molecules does not change their hydration state, and hence the height of the surface-grown polymeric brushes. However, the balance of the intra- and intermolecular interactions is strongly dependent upon the ionic character of the medium between the hydrated chains, modulating the interactions between the zwitterionic PC pendant groups and, consequently, the stiffness of the PMPC molecules in the brush layer
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REF 2028 People, culture and environment survey: UKAPA draft response:
The four UK higher education funding bodies (Research England, SFC, HEFCW and DfE (NI) are publishing key decisions on the high-level design of the next research assessment exercise and outlining issues for further consultation. These decisions represent a shift towards a broader and more holistic approach to research assessment. This survey is hosted by Research England (part of UKRI) on behalf of the four UK funding bodies. The survey is available as a downloadable PDF for convenience (see below).
This is a follow up survey to the initial survey that focuses specifically on the new 'People, Culture and Environment' section of the REF that may replace the Environment section in the individual Units of Assessment including that for Business and Management.
This is the response from UKAPA (United Kingdom Association for Public Administration - the Learned Society for Public Administration)
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